Glass transition of polymers

Dimensional Lattice Model for the Glass Transition of Polymer Melts. A Monte Carlo Simulation. 

Binder, K., Baschnagel, J., Paul, W. Glass transition of polymer melts test of theoretical concepts by computer simulation. Prog. Polymer Sci. (Oxford) 2003, 28, 115-72. 

K. Binder, J. Baschnagel, C. Bennemann, and W. Paul, Monte Carlo and molecular dynamics simulation of the glass transition of polymers, J. Phys. Condens. Matt. 11, A47-A55 (1999). 

The glass transition in a molecular system sets in at the moment the free volume (about 2.5% of the free volume in glass transition of polymers) disappears. Loss of fluidity ( glass transition ) in suspensions occurs when the free volume of suspensions tends to zero. 

Rostiashvili VG, Irzhak VI, Rosenberg BA (1987) Glass-transition of polymers. USSR Leningrad. Ed Khimiya (in Russian)... 

The phase continuity of the individual polymers strongly affects the glass transition of polymer blends. Like most mechanical properties) the DMS behavior of a material is most strongly influenced by the more continuous phase. 

H. P. Wittman, K. Kremer, and K. Binder, /. Chem. Phys., 96, 6291 (1992). Glass Transition of Polymer Melts A Two-Dimensional Monte Carlo Study in the Framework of the Bond Fluctuation Method. 

Factors Affecting the Glass Transition of Polymers Problem Sets... 

The influence of factors such as chemical structure, molecular weight, cross-linking and plasticizers in the glass transition of polymers can be related to the changes that they provoke on the free volume fraction, which, as we already know, reaches a critical value at the glass transition temperature. The factors affecting the glass transition can be classified into two types (1) molecular factors, i.e., those related to the chemical structure of the polymer chain, and (2) external or controllable factors. 

The glass transition of polymers is easily characterized by thermal analysis. A sharp increase in heat capacity on unfreezing over a narrow temperature region is observed. At... 

Condo PD, Paul RD, Johnston KP. Glass transitions of polymers with compressed fluid diluents Type II and type III behavior. Macromolecules 1994 27 365-371. 

It is known that Simha and Boyer (24), treating the glass transition of polymers as an iso-free volume state, have derived the equation ... 

Heat capacity estimates may be made using DTA. In the ideal system, with identical reference and sample materials, the true baseline of the instrument is obtained. Using a reference and sample of different heat capacities, the baseline will not be the same and an estimate of the heat capacity of an unknown may be obtained by comparing the baseline shift with that for a sample of known heat capacity. A shift in the baseline is almost always observed after a DTA peak because of change in heat capacity of the sample. In addition, some reactions such as the glass transition of polymers yield virtually no DTA peak, but there is a rather sharp shift in the baseline after the transition temperature. 

Glass Transition of Polymer Thin Films in the Nanosecond Region. 128... 

Ellison, C. J., Ruszkowski, R. L., Fredin, N. J., and Torkelson, J. M., Dramatic reduction of the effect of nanoconflnement on the glass transition of polymer films via addition of smaU-molecule diluent, Phys. Rev. Lett., 92, 095702-1 to 095702-4 (2004). 

Tsui, O. K. C., Russell, T. R, and Hawker, C. J., Effect of interfacial interactions on the glass transition of polymer thin films. Macromolecules, 34, 5535-5539 (2001). 

As a result, the Autovibron has expanded capability, not only for measurements of the dynamic mechanical properties of materials, but also as a thermal analyzer. The glass transition of polymers can be determined by the loss tangent peak parameters, such as the maximum in loss tangent, peak temperature, and widths of tan 6 peak. 

Tg is the glass transition temperature of the blend, Tg is the glass transition temperature of the pure polymer 1, Tg is the glass transition temperature of the pure polymer 2, K is the ratio of the difference between the expansivities above and below the glass transition of polymer 2 and polymer 1, and volume fraction of polymer 2. 

Sect. 7.3. 7.3 For general discussions of the glass transitions of polymer solutions and copolymers see Turi E, ed (1997) Thermal Characterization of Polymeric Materials, 2 ed. Academic Press, San Diego. 

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